Rotary internal-combustion engine



Nov. 4, 1930. o. scHUMANN ROTARY INTERNAL COMBUSTION ENGINE Filed May 25, 1928 Imi Patented Nov. 4, 1930 UNITED STATES OTTO W. SCHUMANN, OF MAGDEBURG, GERLIANY RTABY INTEBN'AL-COMBUSTION ENGINE,

Applicationlled lay 25, 1928, Seriai No. 230,627, and in Germany June 14, 1927.

This invention relates to rotary intern-al combustionengines, in which either an eccentrically arranged circular rotary piston rotates in a stationary cylinder or casing, or

in which the cylinder or casing rotates around an appropriately arranged stationary circular piston. There are provided, of course, the necessary means for supplying fuel,'as well as air, also for permitting compression of this latter in the proper intervals of time and for injecting the fuel into the v cpressed air, all as fully described herein- The invention is illustrated dia ammatically and by way of example on t e accompanying drawing'on which Figure 1 is an axial section through a rotary internal combustion engine designed according to this invention, this figure showing a constructional form in which the pistons (an aircompressing piston and a working piston) are rotating in a stationary casing; Figure 2 is a crosssection in the plane II--II of Fig. 1, Fi re 3 a cross-section in the plane III- III o Fig. 1, Figure 4 a cross-section through a constructonal form in which the piston is stationary and the cylinder or casing rotates around this piston, this figure being drawn to a reduced scale relatively to Figs. 1-3, Figure 5 shows merely the shaft of another modification, in which two air-compressing pistons and two working pistons are provided, the respective engine being a two-stage one, Figure 6 shows some details of another modification in which the fuel is injected not approximately parallel to the shaft, as in Fig. 1, but approximately at right angles thereto, i. e. practically vertically, and. Figure 7 is a separate view of the fuel feeding pump which is shown in vertical section, the plane of the section passing through the axis of the shaft of the engine.

If the engine is a two-stage one, as indicated by the detail Figure 5, it has two airpistons 1 and 2, preferably of equal size, and two4 working pistons 3 and 4, preferably of unequal size, the smaller of them being the high-pressure piston, the larger the low-pressure one. In the constructional form shown' in Figs. 1-3 there is only one air-piston 1 and one working piston 3, the former rotating in the cylinder 5, the other in the cylinder @which both are located in a common casing 15 provided with cooling spaces 16. The

pistons 1 and 3 are aixed to, or made integral with, a shaft13 by which the power generated is transmitted in known manner. Each pis- A t0n co-operates with a slide 7 arranged above 1t and in the ca'sin 15 and serving to separate the suction-space rom the compression space. The slides are subjected to the ressure of springs 17 which keep the lower f) slide in contact withthe circumferential surfacel of the respective piston.

The air enters into the cylinder 5 through a branch 12 (Fig. 3) Hcovered with@l sieve or piece of wire-netting 12a and the compressed air passes from the cylinder 5 to the cylinder 6 through a passage 11 which terminates in a transverselylocated chamber 8y (Figs. 1

and 2) which serves as mixing chamberl for the air rand the fuel. This latter is injected into said chamber by means of a nozzle 10 supplied with the fuel by the ump 9, which is described separately in the next paragraph. The waste gases escape through the` branch 14 (Fig. 2). The fuel pump may be actuated by the shaft 13 by the intermediary of an eccentric 18 (Fig. 1) or may have driving means of its own. 4The passage 11 for the compressed air from the cylinder 5 into the e mixing chamber 8 can be controlled by a slide-valve 15 controlled by an eccentric 19. Also this Valve is subjected to the pressure of a spring 1 7.

The pump comprises v a plunger 2O which is reciprocated bythe eccentric 18 by the ace of each' intermediary of a' shiftable member 19 oper- 4ated by the control device of the pump. This .1c`al compression spring 21 which is compressed inthe position shown in Fig. 7; in this position the plunger-is in itsl highest position. The pump comprises, besides the plunger, a suction valve 23 and a delivery engine. In therst and the second case all light and heavy liquid fuels, also solid fuels in pulverulent or other form, may be used, whereas in the third case (low-pressure engines) chiefly light liquid fuels are employed. The air is compressed, as the case maybe, to from 4 to 12 atmospheres. The igniting dey vice by which the mixture of the liquid fuel and the air is ignited already in the chamber 8 or only in the cylinder 6 may be of any desired type.

A medium-pressure engine has generally two air pistons (1 and 2, Fig. 5)l and two working pistons (3 and 4, Fig. 5), and a high-pressure engine may also have two or even more than two pistons of each kind. I have abstained from showing'and describing in detail also such rotary internal combustion engines, in that their construction and manner of operation, apart from the number of the pistons and the appertaining cylinders, is the same as already described on the preceding pages.

Concerning the control member 15 which is intended to control the flow of the compressed air on its way from the `cylinder 5 to the chamber 8, I wish it to be understood that it mayV also be so designed as to serve as a means for preventing the combustible mixture from owing back through the pasl sage 11 into the cylinder 5.

It depends upon the number of revolutions of the engine whether vthe engine is so designed that the air piston is, or the air pistons are, leading with respect to the working piston or pistons, or whether the reverse takes place. a A

The pistons 1 and 3 may extend to opposite directions relatively to the shaft 13 so as to balance one another; this is true also of engines having two or more air pistons and two or more working pistons.- What I have said concerning the balancing'of the pistons is true also of the balancing of rotary control members and the like, where such ones are provided. I mention also the point that it is not indispensably requisite that the airv piston and the workingpiston are arranged co-axially; they may be arranged side by side, 1there being then two parallel shafts which may be coupled with each other in any desired manner. I also do not Alimit myself tothe circular shape of the pistons as shown by way of example on the drawing. Also other shapes are possible, especiallyy if two or more cycles are to be carried out at one revolution, as has already been mentioned.

Cooling the engine may be effected by means of water or another cooling liquid or by means of air. yAlso the Ipistons and the shaft can be cooled if they are hollow.

It has already been mentioned in the introductory part of this specification that the pistons may be stationary and the cylinder may rotate. An example for such a constructional form is shown quite diagrammatically in Fig. 4, in which similar numerals of reference denote similar parts as in the other figures, except the numeral 2O which indicates a pulley firmly connected with the rotary cylinder 15, and the numeral 21 which indicates a belt by which the power is transmitted to any machine or the like.

By way of supplement I still mention that the chamber 8 should have practically no corners and no clearance, and should c-.ummuni cate with the cylinder 6 through a narrow slot directed in the direction of rotationl of the'piston 3. The nozzle 10 is preferably shaped as along cone having a rounded-off. end provided with the injection bores. lu the case of two or more nozzles arranged side by side, their bores are preferably so arranged that they all together produce a fanlike jet, as in Fig. 6. Prior to introducing the fuel into the air this latter is used for scavenging the cylinder, as ordinarilyl donih also with ordinary piston internal combustion engines.

I claim:

y 1. A rotary internal combustion engine, comprising, in combination, a casing forming two chambers; a. shaft traversing said chambers; two circular pistons affixed to said shaft in said chambers, one of them being larger than the other and serving to compress air, the other being adapted to be driven round in the appertaining chamber by the explosions; a passage provided in said casing and so located as to conduct the compressed air from the' chamber enclosing said larger chamber to the other chamber; a valve inserted into this passage; means for actuating said valve in correspondence with the revolutions of said two pistons; and a fuel nozzle terminatingI opposite the end of said compressed-air passage at the chamber enclosing the smaller piston, substantially as set forth.

2. A rotary internal combustion engine, comprising, in combination, a casing forming two cylindrical chambers located side by side; a shaft traversing said. chambers in the centres thereof; two circular pistons secured excentrioally to said shaft and being adapted to travel round in their respective chambers, of which one serves as air compression chamber and the other as working chamber; a passage extending in said ings each an upwar p shafttraversing said chambers in the centres casing from the air compression chamber to the workin chamber, and a fuel nozzle also extending into the latter'chamber opposite thereof; two circular pistons attached to said shaftinside said chambers and adapted to travelround in them and around said shaft slides located in said chamber extensions and contactingv at one end with said pistons; means keeping said slides in contact with the said pistons at every position thereof; apasz l. sa e extending in sa1d casing from one of (All sa1d chambers to the other and serving to conduct compressed air from the rst chamber into thev other; a control-valve in said passa e, andl automatic means for actuating this va ve; and a fuel nozzle terminatin into said other cylinder opposite the end o the said 4 passa e, substantially as set forth.

- 4. rotary internal combustion engine, comprising, in combination, a casing forming two chambers adapted to form cylinders for rotating' pistons; a shaft extending" through the 'centres of said chambers or cyl- L? inders; a smaller circular piston and a larger circular iston secured to said shaft within the. cham ers, this piston being adapted to compress air and the /other piston being adapted to' be rotated vby the explosions; a-

passage extending from the` compressed-air chamber tothe vworking chamber, and an extension of said passage, this extension extending along the smaller piston path parallel to the said shaft and having a slot opening into the chamber pertaining to this piston; a

fuel nozzleterminating into said passage extension opposite'thejsaid passage itself, and means for controlling the ow of the compressed air through the said passage, substantially as set forth.

. 5. A rotary internalv combustion Aengine, comprising, in combination, a casmg forming two cylinders adapted. to receive rotary .l pistons a ,shaft` extending through .said cylinders andrtwoI pistons of different" size afl fixed to said shaft' infthe said cylinders;

slides arranged in extensions of the cylinders and contacting at one end with the saidvpistons; springs pressingsaid slides continual-` ly onto the circumferential surface of the Y Pistons; a ompnssed'afir PaSSllg'extending from the one cyhnder to theaother and. en

`tending further along the respective cylinder parallel to thev shaft; and a control' piston e arranged between said slides, and means-for v actuatm said control-piston automatically, substantially as set fort In testimony whereof I aix my signature.

AOTTWO W. SCHUMANN. 

